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Revenue Derived From Services, Percentage

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Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Interest and debt related expenses associated with nonoperating financing activities of the entity.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The net result for the period of deducting operating expenses from operating revenues.

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Cash received for the settlement of litigation during the current period.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Segment Information (Details) $ in Millions	3 Months Ended			6 Months Ended
Segment Information (Details) $ in Millions	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) segment	Sep. 30, 2015 USD ($)
Segment Reporting [Abstract]
Number of operating segments \| segment				2
Revenues
Total Revenues	$ 49,957	$ 48,761		$ 99,690	$ 96,307
Operating profit
Total	580	954		1,552	1,885
Interest Expense	(78)	(91)		(157)	(180)
Income from Continuing Operations Before Income Taxes	525	880		1,437	1,735
Gain on disposition of business				(113)	102
Goodwill impairment charge	290	0		290	0
Total Distribution Solutions
Operating profit
Goodwill impairment charge				0
Technology Solutions
Operating profit
Goodwill impairment charge	290			290
Operating Segments
Revenues
Total Revenues	49,957	48,761		99,690	96,307
Operating profit
Total	677	1,072		1,773	2,140
Operating Segments \| Total Distribution Solutions
Revenues
Total Revenues	49,277	48,040		98,286	94,850
Operating profit
Total	$ 851	$ 926		$ 1,779	$ 1,836
Revenue derived from services, percentage (less than)	2.00%	2.00%		2.00%	2.00%
Proceeds from legal settlements				$ 142	$ 59
Operating Segments \| Total Distribution Solutions \| ZEE Medical Business
Operating profit
Gain on disposition of business		$ 52
Operating Segments \| Total Distribution Solutions \| LIFO Method of Accounting
Operating profit
Total	$ 43	(91)		(4)	(182)
Operating Segments \| Total Distribution Solutions \| Reportable Subsegments \| North America pharmaceutical distribution and services
Revenues
Total Revenues	41,375	40,603		82,586	80,135
Operating Segments \| Total Distribution Solutions \| Reportable Subsegments \| International pharmaceutical distribution and services
Revenues
Total Revenues	6,271	5,866		12,601	11,704
Operating Segments \| Total Distribution Solutions \| Reportable Subsegments \| Medical-Surgical distribution and services
Revenues
Total Revenues	1,631	1,571		3,099	3,011
Operating Segments \| Technology Solutions
Revenues
Total Revenues	680	721		1,404	1,457
Operating profit
Total	(174)	146		(6)	304
Operating Segments \| Technology Solutions \| Nurse Triage
Operating profit
Gain on disposition of business			$ 51		51
Corporate
Operating profit
Corporate Expenses, Net	$ (74)	$ (101)		$ (179)	$ (225)